GillTrading.com of Beaverton makes and markets a variety of automated cleaning systems for industrial-sized troughs, weir clarifiers and tanks. It has several product lines, including the WeirWasher.

The company says it engineers its weir washers to the size and shape of its customers' tanks. The machine blasts pressurized streams of water onto areas that are difficult to clean. "No brush, no sweeping" says the video's tagline.

Here's a three-page description of the use of a WeirWasher to limit the growth of algae and snails in a Connecticut city's wastewater treatment plant. It concludes that the use of the device saved staff time.